226 research outputs found
Treatment fidelity in the Camden Weight Loss (CAMWEL) intervention assessed from recordings of advisor-participant consultations.
BACKGROUND: Variations in the delivery of content and process can alter the effectiveness of complex interventions. This study examined the fidelity of a weight loss intervention (Camden Weight Loss) from recorded consultations by assessing advisors' delivery of content, use of motivational interviewing approach and therapeutic alliance. METHODS: A process evaluation was conducted of advisor-participant consultations in a 12-month randomised controlled trial of an intervention for adult volunteers with a body mass index categorised as overweight or obese. A convenience sample of 22 consultations (12% of 191 participants) recorded at the intervention mid-point were available for analysis. Consultations were independently rated by two observers independent of intervention or study delivery, using: a fidelity scale, the Motivational Interviewing Treatment Integrity Scale and the Primary Care Therapy Process Rating Scale. Raters were blind to participants' responses to the intervention and weight outcomes. Half the participants (N = 11) achieved significant weight loss (≥ 5% of baseline weight). RESULTS: A mean of 41% of prescribed content was delivered, with a range covered per session of 8-98%, falling below the 100% content expected per session. Tasks included most frequently were: taking weight and waist measurements (98%), scheduling next appointment (86%), review of general progress (85%) and reviewing weight change (84%). Individual items most frequently addressed were 'giving encouragement' and 'showing appreciation of participant's efforts' (95 and 88% respectively). Consultation length (mean 19 min, range 9-30) was shorter than the 30-min allocation. Quantity of content correlated with consultation length (p < 0.01). Advisors' use of motivational interviewing was rated at 'beginner proficiency' for Global Clinician Rating, Reflection to Question Ratio and Percent Open Questions. Therapeutic alliance scores were moderate. Affective aspects were rated highly (e.g. supportive encouragement, involvement and warmth). CONCLUSIONS: Intervention fidelity varied in both content and process, emphasising the importance of ongoing fidelity checks in a complex intervention. Advisors focused on certain practical aspects of the intervention and providing an encouraging interpersonal climate. This concurs with other research findings, which have revealed the value participants in a weight loss intervention place on an empathic advisor-participant relationship. CLINICAL TRIALS REGISTRATION: Registered with Clinicaltrials.gov, number NCT00891943, on 1 May 2009
Scope actuation system for articulated laparoscopes
Background: An articulated laparoscope comprises a rigid shaft with an articulated distal end to change the viewing direction. The articulation provides improved navigation of the operating field in confined spaces. Furthermore, incorporation of an actuation system tends to enhance the control of an articulated laparoscope. Methods: A preliminary prototype of a scope actuation system to maneuver an off-the-shelf articulated laparoscope (EndoCAMaleon by Karl Storz, Germany) was developed. A user study was conducted to evaluate this prototype for the surgical paradigm of video-assisted thoracic surgery. In the study, the subjects maneuvered an articulated scope under two modes of operation: (a) actuated mode where an operating surgeon maneuvers the scope using the developed prototype and (b) manual mode where a surgical assistant directly maneuvers the scope. The actuated mode was further assessed for multiple configurations based on the orientation of the articulated scope at the incision. Results: The data show the actuated mode scored better than the manual mode on all the measured performance parameters including (a) total duration to visualize a marked region, (a) duration for which scope focus shifts outside a predefined visualization region, and (c) number of times for which scope focus shifts outside a predefined visualization region. Among the different configurations tested using the actuated mode, no significant difference was observed. Conclusions: The proposed articulated scope actuation system facilitates better navigation of an operative field as compared to a human assistant. Secondly, irrespective of the orientation in which an articulated scope’s shaft is inserted through an incision, the proposed actuation system can navigate and visualize the operative field
A generic scope actuation system for flexible endoscopes
Background: A scope actuation system assists a surgeon in steering a scope for navigating an operative field during an interventional or diagnostic procedure. Each system is tailored for a specific surgical procedure. The development of a generic scope actuation system could assist various laparoscopic and endoscopic procedures. This has the potential to reduce the deployment and maintenance costs for a hospital, making it more accessible for clinical usage. Methods: A modular actuation system (for maneuvering rigid laparoscopes) was adapted to enable incorporation of flexible endoscopes. The design simplifies the installation and disassembly processes. User studies were conducted to assess the ability of the system to focus onto a diagnostic area, and to navigate during a simulated esophagogastroduodenoscopy procedure. During the studies, the endoscope was maneuvered with (robotic mode) and without (manual mode) the actuation system to navigate the endoscope’s focus on a predefined track. Results: Results show that the robotic mode performed better than the manual mode on all the measured performance parameters including (a) the total duration to traverse a track, (b) the percentage of time spent outside a track while traversing, and (c) the number of times the scope focus shifts outside the track. Additionally, robotic mode also reduced the perceived workload based on the NASA-TLX scale. Conclusions: The proposed scope actuation system enhances the maneuverability of flexible endoscopes. It also lays the groundwork for future development of modular and generic scope assistant systems that can be used in both laparoscopic and endoscopic procedures
Triangulations and Severi varieties
We consider the problem of constructing triangulations of projective planes
over Hurwitz algebras with minimal numbers of vertices. We observe that the
numbers of faces of each dimension must be equal to the dimensions of certain
representations of the automorphism groups of the corresponding Severi
varieties. We construct a complex involving these representations, which should
be considered as a geometric version of the (putative) triangulations
Treatment fidelity in the Camden Weight Loss (CAMWEL) intervention assessed from recordings of advisor-participant consultations
BACKGROUND:
Variations in the delivery of content and process can alter the effectiveness of complex interventions. This study examined the fidelity of a weight loss intervention (Camden Weight Loss) from recorded consultations by assessing advisors’ delivery of content, use of motivational interviewing approach and therapeutic alliance.
METHODS:
A process evaluation was conducted of advisor-participant consultations in a 12-month randomised controlled trial of an intervention for adult volunteers with a body mass index categorised as overweight or obese. A convenience sample of 22 consultations (12% of 191 participants) recorded at the intervention mid-point were available for analysis. Consultations were independently rated by two observers independent of intervention or study delivery, using: a fidelity scale, the Motivational Interviewing Treatment Integrity Scale and the Primary Care Therapy Process Rating Scale. Raters were blind to participants’ responses to the intervention and weight outcomes. Half the participants (N = 11) achieved significant weight loss (≥ 5% of baseline weight).
RESULTS:
A mean of 41% of prescribed content was delivered, with a range covered per session of 8–98%, falling below the 100% content expected per session. Tasks included most frequently were: taking weight and waist measurements (98%), scheduling next appointment (86%), review of general progress (85%) and reviewing weight change (84%). Individual items most frequently addressed were ‘giving encouragement’ and ‘showing appreciation of participant’s efforts’ (95 and 88% respectively). Consultation length (mean 19 min, range 9–30) was shorter than the 30-min allocation. Quantity of content correlated with consultation length (p < 0.01). Advisors’ use of motivational interviewing was rated at ‘beginner proficiency’ for Global Clinician Rating, Reflection to Question Ratio and Percent Open Questions. Therapeutic alliance scores were moderate. Affective aspects were rated highly (e.g. supportive encouragement, involvement and warmth).
CONCLUSION:
Intervention fidelity varied in both content and process, emphasising the importance of ongoing fidelity checks in a complex intervention. Advisors focused on certain practical aspects of the intervention and providing an encouraging interpersonal climate. This concurs with other research findings, which have revealed the value participants in a weight loss intervention place on an empathic advisor-participant relationship
Spin Foams and Noncommutative Geometry
We extend the formalism of embedded spin networks and spin foams to include
topological data that encode the underlying three-manifold or four-manifold as
a branched cover. These data are expressed as monodromies, in a way similar to
the encoding of the gravitational field via holonomies. We then describe
convolution algebras of spin networks and spin foams, based on the different
ways in which the same topology can be realized as a branched covering via
covering moves, and on possible composition operations on spin foams. We
illustrate the case of the groupoid algebra of the equivalence relation
determined by covering moves and a 2-semigroupoid algebra arising from a
2-category of spin foams with composition operations corresponding to a fibered
product of the branched coverings and the gluing of cobordisms. The spin foam
amplitudes then give rise to dynamical flows on these algebras, and the
existence of low temperature equilibrium states of Gibbs form is related to
questions on the existence of topological invariants of embedded graphs and
embedded two-complexes with given properties. We end by sketching a possible
approach to combining the spin network and spin foam formalism with matter
within the framework of spectral triples in noncommutative geometry.Comment: 48 pages LaTeX, 30 PDF figure
Trace as an alternative decategorification functor
Categorification is a process of lifting structures to a higher categorical
level. The original structure can then be recovered by means of the so-called
"decategorification" functor. Algebras are typically categorified to additive
categories with additional structure and decategorification is usually given by
the (split) Grothendieck group. In this expository article we study an
alternative decategorification functor given by the trace or the zeroth
Hochschild--Mitchell homology. We show that this form of decategorification
endows any 2-representation of the categorified quantum sl(n) with an action of
the current algebra U(sl(n)[t]) on its center.Comment: 47 pages with tikz figures. arXiv admin note: text overlap with
arXiv:1405.5920 by other author
Changes in synaptic transmission and protein expression in the brains of adult offspring after prenatal inhibition of the kynurenine pathway
During early brain development, N-methyl-d-aspartate (NMDA) receptors are involved in cell migration, neuritogenesis, axon guidance and synapse formation, but the mechanisms which regulate NMDA receptor density and function remain unclear. The kynurenine pathway of tryptophan metabolism includes an agonist (quinolinic acid) and an antagonist (kynurenic acid) at NMDA receptors and we have previously shown that inhibition of the pathway using the kynurenine-3-monoxygenase inhibitor Ro61-8048 in late gestation produces rapid changes in protein expression in the embryos and effects on synaptic transmission lasting until postnatal day 21 (P21). The present study sought to determine whether any of these effects are maintained into adulthood. After prenatal injections of Ro61-8048 the litter was allowed to develop to P60 when some offspring were euthanized and the brains removed for examination. Analysis of protein expression by Western blotting revealed significantly reduced expression of the GluN2A subunit (32%) and the morphogenetic protein sonic hedgehog (31%), with a 29% increase in the expression of doublecortin, a protein associated with neurogenesis. No changes were seen in mRNA abundance using quantitative real-time polymerase chain reaction. Neuronal excitability was normal in the CA1 region of hippocampal slices but paired-pulse stimulation revealed less inhibition at short interpulse intervals. The amount of long-term potentiation was decreased by 49% in treated pups and recovery after low-frequency stimulation was delayed. The results not only strengthen the view that basal, constitutive kynurenine metabolism is involved in normal brain development, but also show that changes induced prenatally can affect the brains of adult offspring and those changes are quite different from those seen previously at weaning (P21). Those changes may be mediated by altered expression of NMDAR subunits and sonic hedgehog
The Edinburgh Social Cognition Test (ESCoT):Examining the effects of age on a new measure of theory of mind and social norm understanding
<div><p>Current measures of social cognition have shown inconsistent findings regarding the effects of healthy aging. Moreover, no tests are currently available that allow clinicians and researchers to examine cognitive and affective theory of mind (ToM) and understanding of social norms within the same test. To address these limitations, we present the Edinburgh Social Cognition Test (ESCoT) which assesses cognitive and affective ToM and inter- and intrapersonal understanding of social norms. We examined the effects of age, measures of intelligence and the Broader Autism Phenotype (BAP) on the ESCoT and established tests of social cognition. Additionally, we investigated the convergent validity of the ESCoT based on traditional social cognition measures. The ESCoT was administered alongside Reading the Mind in Films (RMF), Reading the Mind in Eyes (RME), Judgement of Preference and Social Norm Questionnaire to 91 participants (30 aged 18–35 years, 30 aged 45–60 years and 31 aged 65–85 years). Poorer performance on the cognitive and affective ToM ESCoT subtests were predicted by increasing age. The affective ToM ESCoT subtest and RMF were predicted by gender, where being female predicted better performance. Unlike the ESCoT, better performance on the RMF was predicted by higher verbal comprehension and perceptual reasoning abilities, while better performance on the RME was predicted by higher verbal comprehension scores. Lower scores on inter-and intrapersonal understanding of social norms were both predicted by the presence of more autism-like traits while poorer interpersonal understanding of social norms performance was predicted by increasing age. These findings show that the ESCoT is a useful measure of social cognition and, unlike established tests of social cognition, performance is not predicted by measures of verbal comprehension and perceptual reasoning. This is particularly valuable to obtain an accurate assessment of the influence of age on our social cognitive abilities.</p></div
Vacuum-assisted breast biopsy: A comparison of 11-gauge and 8-gauge needles in benign breast disease
© 2008 Hahn et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
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